A common form of surface finish for ceilings, especially within commercial construction is the “dropped ceiling.” With a dropped ceiling a lattice of T-bars is suspended at a height desired for the ceiling. Ceiling tiles are provided which have a size and shape matching gaps in this lattice of T-bars. These ceiling tiles are placed within these gaps to fill these gaps between the T-bars. The T-bars generally have a shape with a vertically extending spine portion and a horizontally extending rest shelf so that the T-bar is generally in the form of an upside down “T.”
Lighting for interior building spaces can be provided in a variety of different ways. Often the most effective lighting for an interior space is overhead lighting. In a commercial environment where rooms are typically quite large, it is often advantageous to suspend lighting from the ceiling or embed lighting within the ceiling. When the ceiling includes a “dropped ceiling” arrangement, often some of the gaps in the lattice of T-bars are filled with lighting bays. For instance, fluorescent light tubes can reside within lighting bays that are sized to fill typical gaps within the T-bar lattice. Thus, rather than place a ceiling tile within certain gaps, lighting bays are installed.
An important consideration in the design and construction of buildings is the energy utilized by such buildings. One major factor in energy consumption of a building is the efficiency with which the space is heated and cooled. When the space utilizes a dropped ceiling, typically the conditioned space is only that space below the ceiling tiles of the“dropped ceiling.” Heating, ventilating and air conditioning (HVAC) ducts can be mounted in gaps between T-bars within the lattice forming the dropped ceiling in place of a ceiling tile, to deliver conditioned air into the conditioned space within the building. Space above the dropped ceiling typically has an undesirably hot or cold temperature compared to the conditioned space below. To enhance the effectiveness of HVAC systems in such buildings, ceiling tiles typically have a degree of resistance to heat transfer therethrough, such that temperature differentials between space above the dropped ceiling and conditioned space below the dropped ceiling can be efficiently maintained.
An additional source of power consumption within a building is the power consumed by lighting. Not only does lighting within a building directly affect energy consumption due to the power utilized to drive the light sources, but also lighting often generates significant heat within the conditioned space which then must be transferred from the space when the space is experiencing an unacceptably high temperature. Prior art attempts to reduce the energy consumption associated with lighting have included use of lower power higher efficiency lighting sources, such as fluorescent lighting and light emitting diode (LED) lighting. Beneficially, such alternative lighting sources both require less power to drive the light sources, and also typically generate less heat, minimizing heat sources which the HVAC systems of the building thus need to contend with. LED lighting also typically has a longer life than other lighting technologies.
One problem that is generated by utilization of LED lightings in particular, is that while a relatively low amount of heat is generated by the LED lighting, this heat is concentrated in a particularly small space directly adjacent the LED electronics required to generate the light. A major factor in the operating life of such LED lighting is the degree to which this heat can be effectively dissipated to avoid excessive heating of the electronics associated with the LED and other components of the LED which experience a shorter operational life when excess temperatures are experienced. Accordingly, a need exists for heat management associated with LED lighting, particularly when LED lighting is incorporated into a dropped ceiling of a building. Secondarily, other light sources and other sources of heat can benefit from having heat associated therewith transferred out of the conditioned space within a building, rather than the heat adding to the heat load within the conditioned space and requiring additional load on the HVAC equipment within the building.